<template>
  <div id="app">
    <h2>加法测试题</h2>
    <subject v-for="(result,index) in list"
    :key="index"
    :index="index"
    @result="resultFn"
    ></subject>
    <div>
      <flag v-for="(result,index) in list"
      :key="index"
      :result="result"
      :index="index"
      ></flag>
    </div>
  </div>
</template>

<script>
import subject from './components/Subject'
import flag from './components/Flag'
export default {
  components:{
    subject,
    flag
  },
  data(){
    //需要替换情况，用索引值
    return{
      list:["未完成","未完成","未完成","未完成","未完成",] //保存题目的结果，有三种情况
    }
  },
  methods:{
    resultFn(resultStr,index){
        this.$set(this.list,index,resultStr)//结果更新
    }
  }
};
</script>

<style>
body {
  background-color: #eee;
}

#app {
  background-color: #fff;
  width: 500px;
  margin: 50px auto;
  box-shadow: 3px 3px 3px rgba(0, 0, 0, 0.5);
  padding: 2em;
}
</style>